In a number of mechanical systems, as, for example, aircraft actuation systems, it is necessary to cause two simultaneous movements to occur in which a first body is moved during the first portion of travel of a second body, but the first body stops while the second body continues to travel. For example, in separate but related actuation systems such as, door/spoiler systems, it is necessary to cause simultaneous movements of the door and the spoiler and, after a preselected period of time, to stop movement of the spoiler while the door continues to move.
Typically, these separate but related actuation systems have required either separate power drive units (prime movers) or mechanical shifting devices. The use of separate power drive units is undesirable in terms of weight, volume and interface/mounting complexity. The conventional mechanical shifting devices have inherent sequencing, timing and dynamic load problems.
The present invention is directed to a mechanical mode shifter which solves the problems associated with the conventional mechanical shifting devices, identified above.